So this is definitely an oversight and not what we intended. We are going to change the price point to 475 to match the $4.99 coin package as soon as we can and we will be rolling out a refund to all people who purchased the bundle at the 490 coin point. Hoping this price change will be able to go live today, tomorrow at the latest. The refund would role out a little later this week. We are working on this now.
Edit: to clarify - we will refund the 15 coins overage, not the full amount. We still need your bundle purchasing support 😬